Method for assembling tone hole closing means of wood-wind musical instruments and a construction of the means assembled thereby

ABSTRACT

An air-tight sealing of a pad closing a tone hole of a wind instrument is much facilitated by interposing a foamable thermosetting plastic resin preimpregnated sheet between the bottom wall of a cup and the pad, and heating the preimpregnated sheet thus interposed, so that the sheet is foamed and cured while the pad is maintained in a closed condition over the tone hole of the wind instrument, whereby the pad can be assembled in the cup so as to close the tone hole with sufficient airtightness without requiring any repeated adjustments of the relative positions between the pad and the cup.

United States Patent Matsuura et ai.

METHOD FOR ASSEMBLING TONE HOLE CLOSING MEANS OF WOOD- WIND MUSICAL INSTRUMENTS AND A CONSTRUCTION OF THE MEANS ASSEMBLED THEREBY inventors: IIideo Matsuura, i-lamakita; lknli Kuroitawa; Yoshihiko Murase, both of Hamamatsu, all of Japan Assignee: Nippon Gakki Seizo Kabushiki Kaisha, Hamarnatsu-shi, Japan Filed: Aug. 27, 1970 Appl. No.: 67,485

Foreign Application Priority Data Sept. I, 1969 Japan ..44/692l5 US. Cl ..84/380 Int. Cl. ..G 10d 7/00 Field of Search ..84/380, 385.]

[451 Sept. 19, 1972 Primary Examiner-Richard B. Wilkinson Assistant Examiner-Lawrence R. Franklin Attorney-Ostrolenlt, Faber, Gerb 8L Soffen [57] ABSTRACT An air-tight sealing of a pad closing a tone hole of a wind instrument is much facilitated by interposing a foamable thermosetting plastic resin preimpregnated sheet between the bottom wall of a cup and the pad. and heating the preimpregnated sheet thus interposed. so that the sheet is foamed and cured while the pad is maintained in a closed condition over the tone hole of the wind instrument, whereby the pad can be assembled in the cup so as to close the tone hole with sufficie'nt airtightness without requiring any repeated adjustments of the relative positions between the pad and the cup.

3 Claims, 3 Drawing Figures PATENTEDSEHQ m2 3.691.892

INVENTORS M050 MATjUU/PA yam/Mm Mmwf ATTORNEY? METHOD FOR ASSEMBLING TONE HOLE CLOSING MEANS OF WOOD-WIND MUSICAL INSTRUMENTS AND A CONSTRUCTION OF THE MEANS ASSEMBLED THEREBY BACKGROUND OF THE INVENTION This invention generally relates to a method and construction of tone hole closing means for wood-wind musical instruments facilitating the alignment with the tone holes, and more particularly to a method and construction of tone hole closing means to be employed in wood-wind musical instruments such as a flute, clarinet, and oboe wherein the alignment and airtightness of the pads to the upper circumferential edges of the tone holes at the time of the closure of the tone holes by these closing means are much facilitated.

Tone hole closing means are provided in a woodwind musical instrument for allowing to open or close the tone holes selectively so that a desired rendition of music can be thereby attained, and in such cases, a complete and air-tight closure thereof greatly affects the tone pitch, the tone intensity, and the tone color produced from the wood-wind instrument. In the closed condition, the pad of the closing means must be abutting correctly the upper circumferential edge of each of the tone holes, and this condition must be maintained for a long working life of the instrument without causing misalignment and deformation of the pad despite the severe and frequent closing and opening operations of the tone hole closing means.

Conventionally constructed tone hole closing means has included a tray-like cup pivotally mounted on a side portion of each of the tone holes, and a pad consisting of felt or the like wrapped by a fish skin and held within the cup by means of a centrally located washer and a machine screw, as will be described hereinafter in more detail. In such a construction, the vertical position and the inclination of the pad with respect to the upper circumferential edge of the tone hole, in other words the vertical alignment of the pad, must be adjusted employing a liner material such as thick paper, so that the outer surface of the pad contacts the whole circumference of the tone hole simultaneously and a uniform distribution of the contact pressure is maintained along the whole circumference at the time the tone hole closing means has closed the tone hole.

For this reason, when the pad is assembled in the cup, a liner material of a seemingly suitable thickness is first inserted between the inner bottom of the cup and the inner surface of the pad, and after the air-tightness between the pad and the tone hole is investigated, the liner material must be adjusted repeatedly, for the complete air-tightness, rendering the assembling work of the pad to be extremely time-consuming and laborious.

SUMMARY OF THE INVENTION Therefore, the primary object of the present invention is to provide an improved method and construction of the tone hole closing means employed in woodwind musical instruments, wherein the assembling of the pad is much simplified than in the conventional construction.

Another object of the present invention is to provide an improved method and construction of the tone hole closing means employed in wood'wind musical instruments such as a flute, clarinet, and oboe, wherein the alignment and airtightness of the pad with respect to the upper circumferential edge of the tone hole is much facilitated.

Still another object of the present invention is to provide an improved method and construction of the tone hole closing means employed in wood-wind instruments, wherein the elastic pad can be permanently maintained at the initially adjusted position and any possibility of accidental misalignment thereof is substantially eliminated.

An additional object of the present invention is to provide an improved method and construction of the tone hole closing means employed in wood-wind instruments, wherein the alignment of the pad is obtained without requiring any repeated adjustment and the mass-production of the wood-wind instruments is thereby made possible.

These and other objects of the invention can be achieved by an improved method and construction of the tone hole closing means employed in wood-wind instruments, wherein at the time of the assembling, a sheet preimpregnated with a foamable plastic substance is interposed between the inner bottom wall of the cup and the rear surface of the pad, and the preimpregnated sheet is thereafter foamed and cured under the closed condition of the pad over the tone hole.

The invention will be better understood from the following description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a perspective view showing a generally used construction of a tone hole closing means employed for opening and closing a tone hole of a wood-wind instrument;

FIG. 2 is a sectional view taken along the line ll-ll of FIG. I and to be employed for the explanation of the conventional construction of the tone hole closing means; and

FIG. 3 is a sectional view similar to FIG. 2 showing an improved construction of the tone hole closing means in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION For better understanding of the improved method and construction according to the present invention for facilitating the assembling work of the pad in the cup, a general construction of the tone hole closing means employed for the wood-wind musical instrument will first be described. Referring to FIGS. 1 and 2, there is indicated a tone hole closing means employed for the wood-wind instrument comprising a tray-shaped cup I, an arm 2 integrally formed at one side of the cup 1, and a pin or shaft 3 rotatably supported by a supporting member (not shown) mounted on the body of the wood-wind musical instrument.

On the lower concaved side of the cup 1, a centrally located projected portion 5 is provided fixedly, and through the vertical axis of the projected portion 5 a threaded hole is bored. A ring-shape pad 4 consisting of, for instance, felt wrapped around by, for instance, a fish skin '7 and an adjustable liner material 6 of, for instance, thick paper are inserted into the concaved side of the tray-shaped cup 1 so that the liner material 6 is interposed between the bottom wall of the tray-shaped cup 1 and the rear side of the pad 4, and both of the materials 4 and 6 are held in position by means of a washer 8 and a machine screw 9.

The tone hole closing means thus assembled may be rotated around its shaft 3 in a vertical plane through a predetermined angle so that the tone hole indicated by chain lines in FIG. 2 is thereby open or closed. When the tone hole closing means is operated to close the tone hole, it is desired that the tone hole is closed in a good air tight manner between the lower surface of the pad and the upper circumferential edge 10 of the tone hole and for the realization of such a condition, the thickness of the liner material 6 is adjusted repeatedly. Because of the requirement of such adjusting works, the conventional construction of the tone hole closing means required much time for its assembling and has been considered to be not adapted for mass-production.

Furthermore, the conventional construction has involved far more possibility of causing deformation and misalignment of the pad during the long working life of the wood-wind instrument.

The present invention is directed to provide an improved method and construction for facilitating the assembling work of the tone hole closing means to be em played in various kinds of wood-wind instruments, whereby the above described drawbacks of the conven tional construction of the closing means can be completely eliminated. The improved construction of the closing means will now be described in more detail with reference made to FIG. 3. According to the present invention, the liner material 6 of thick paper employed in the conventional construction of the closing means is replaced by a foamable preimpregnated sheet or foamable pre-preg 11, and the sheet 11 is thereafter foamed and cured by heat treatment, maintaining the pad 4 in an air-tight closed position with respect to the tone hole, so that the position of the pad 4 is permanently fixed to abut the upper circumferential edge 10 of the tone hole.

In the above description, the preimpregnated sheet or pre-preg is termed to be a material consisting of core substance such as fibrous material impregnated with a thermosetting plastic resin and thereafter partly cured or hardened. Such preimpregnated sheet is cut into a desired shape and size, and the thus cut piece can be cured or hardened completely by heat treatment when it is placed in a confined area. When a foaming agent is further added in the preparation of the preimpregnated sheet or pre-preg, a foamable preimpregnated sheet can be obtained, and this material is employed instead of the conventional liner material such as thick paper. After the assembling of the pad, if the newly employed liner material is heated to a desired temperature, the new material is easily foamed and cured to fill nearby spaces and the pad can be fixed permanently to its correctly aligning position, backed by the foamed sheet. Because of the foaming nature of the newly employed liner material, it will be apparent that the space 12 located above the liner material can be substantially filled with the foamed material and the position of the pad is thereby ensured.

Some of the examples wherein the present invention is put into practice will now be indicated in the following.

EXAMPLE I a. Preparation of the foamable preimpregnated sheet:

Polyester resin (Trade Name Epolac N-3l7 I00 parts by wt. Hardener (benaoyl peroxide) 1 part by wt. Condensing agent (magnesium oxide) 3 parts by Foaming agent (toluenesulfonylhydrazide) 7 parts by wt.

Briding or crosslinking agent (styrene monomer) 15 parts by wt.

The above described materials are mixed together to form a compound-like mixture, 10 times by wt. of the mixture is impregnated into l part by wt. of unwoven cloth (Reemay 2440, Du Pont), both sides of the unwoven cloth being covered by a polyethylene sheet of 0.03 mm thickness for making handling thereof easier and dried out at 60C for 15 minutes.

5. Assembling of the tone hole closing means:

The above described foamable preimpregnated sheet is cut into a doughnut shape and interposed between the bottom wall of the cup 1 and the pad 4 wrapped by the fish skin 7, and both of the members are fixed to their positions by means of a washer 8 and a screw 9.

c. Hardening:

Maintaining the pad 4 thus assembled in its airtightly, closing position over the tone hole of, for example, a flute, the main body of the flute is heated to C for 30 minutes.

d. Results obtained:

After cooled to the room temperature, the flute was taken out of the heating oven and the condition of the pad was examined. As a result, it was found that the pad 4 was seated in a good condition within the cup 1 and the sealing nature of the pad when it closed the tone hole was also excellent.

EXAMPLE 2 In the above described Example 1, 8 wt. parts of azobisisobutyronitrile was added instead of the above described hardener and foaming agent and the pad was also fixed in the same manner. As a result, it was found that the pad could be fixed in a good sealing condition when the tone hole closing means was brought to its closing state over the tone hole.

As is apparent from those described above, the method for assembling tone hole closing means and the construction facilitating the assembling work, both according to the present invention, can eliminate the adjusting process in the production of the wood-wind musical instruments, whereby the production efficiency of the same instruments can be improved remarkably. Furthermore, the durability of the tone hole closing means constructed in accordance with the present invention is far superior to the conventional construction thereof wherein a liner material of, for instance, thick paper has been employed, and because the space between the bottom wall of the cup and the rear surface of the pad is substantially filled with the foamed material, any possibility of causing deformation or misalignment can be eliminated completely.

We claim:

1. A method for assembling a tone hole closing means for a wood-wind musical instrument which closing means comprises a closed end cup and a pad mounted in the cup and which closing means is operative to open and close a tone hole formed on the body of said instrument; said method comprises the steps of interposing a foamable preimpregnated sheet between the cup closed end and the pad, maintaining the cup in a position such that the pad is in a closed position over the tone hole in an airtight sealing manner, and while the cup is so maintained, heating the foamable preimpregnated sheet so that the sheet is foamed and cured.

2. A tone hole closing means for a wood-wind musical instrument comprising a closed end cup, means for connecting said cup to an instrument in a manner to permit said cup to be moved toward and away from a tone hole closing position; a pad mounted in said cup and being formed of a material which is operative to open and close a tone hole formed in the body of an instrument as said cup is moved away from and toward said tone hole closing position; and a foamed sheet interposed between said cup closed end and said pad, said sheet being formed of a heat cured and foamed foamable preimpregnated sheet.

3. The tone hole closing means of claim 2, wherein said foamed sheet is comprised of a core substance of fibrous material which is impregnated with a thermosetting plastic resin and with a foaming agent.

1F I i t i 

1. A method for assembling a tone hole closing means for a woodwind musical instrument which closing means comprises a closed end cup and a pad mounted in the cup and which closing means is operative to open and close a tone hole formed on the body of said instrument; said method comprises the steps of interposing a foamable preimpregnated sheet between the cup closed end and the pad, maintaining the cup in a position such that the pad is in a closed position over the tone hole in an airtight sealing manner, and while the cup is so maintained, heating the foamable preimpregnated sheet so that the sheet is foamed and cured.
 2. A tone hole closing means for a wood-wind musical instrument comprising a closed end cup, means for connecting said cup to an instrument in a manner to permit said cup to be moved toward and away from a tone hole closing position; a pad mounted in said cup and being formed of a material which is operative to open and close a tone hole formed in the body of an instrument as said cup is moved away from and toward said tone hole closing position; and a foamed sheet interposed between said cup closed end and said pad, said sheet being formed of a heat cured and foamed foamable preimpregnated sheet.
 3. The tone hole closing means of claim 2, wherein said foamed sheet is comprised of a core substance of fibrous material which is impregnated with a thermosetting plastic resin and with a foaming agent. 